The growing interest in RNA structure has stemmed from the discovery of catalytic RNA molecules that can fold to form active sites for catalysis of chemical reactions. Group II introns are self-splicing RNAs that are equipped to perform the two step transesterification reaction in both the forward and reverse directions. Reverse splicing by the intron can occur into a DNA or RNA substrate. With the assistance of an intron encoded maturase, the group II intron site-specifically inserts itself into duplex DNA. It is of interest to identify the RNA structural elements required for reverse splicing into DNA. Nucleotide Analog Interference Mapping (NAIM) is a novel chemogenetic approach to biochemically characterize RNA structure. After development of a reverse splicing assay, NAIM will be utilized to understand the chemical basis of group II intron structure and function. The interactions identified using NAIM will increase the understanding of group II intron structure and tertiary contacts at the atomic level. The study of group II intron splicing will yield numerous insights into pre-mRNA splicing, since these two processes are similar. High resolution details of the structure of the group II intron during reverse splicing may allow for development of novel site specific vectors that can be used as genetic agents for the treatment of cancer and viral infections.